Actuation mechanism, downhole device and method

ABSTRACT

Provided is an downhole actuation mechanism, the actuation mechanism comprising: a first part having a guiding surface; a second part defining a passageway; the second part being movable with respect to the guiding surface between a first position and a second position; the second part defining a first clearance of the passageway in the first position; the second part defining a second clearance of the passageway in the second position, the second clearance being larger than the first clearance.

TECHNICAL FIELD

The subject matter disclosed herein relates to the field of actuation mechanisms for usage in a downhole.

BACKGROUND

WO 2019/122004 A2 discloses a downhole catcher device comprising a catching mechanism which is configured to be transferable between a first mode and the second mode. The catching mechanism is further configured for passing by a first operation element if the catching mechanism is in the first mode and for catching a second operation element if the catching mechanism is in the second mode. The transfer between the first and the second mode is triggered by a downhole tool which is operated by the second operation element. The catcher device may comprise a first coupling element for coupling the catching mechanism to a second coupling element of the downhole tool located upstream the catching mechanism. The first coupling element may form at least part of a swivel coupling.

SUMMARY

In view of the above-described situation, there still exists a need for an improved technique that enables to actuate a device, for example a catcher device.

This need may be met by the subject matter according to the independent claims. Advantageous embodiments of the herein disclosed subject matter are described by the dependent claims.

According to a first aspect of the herein disclosed subject matter there is provided a downhole actuation mechanism.

According to an embodiment of the first aspect there is provided a downhole actuation mechanism, the actuation mechanism comprising: a first part having a guiding surface; a second part defining a passageway; the second part being movable with respect to the guiding surface between a first position and a second position; the second part defining a first clearance of the passageway in the first position; the second part defining a second clearance of the passageway in the second position, the second clearance being larger than the first clearance.

According to a second aspect of the herein disclosed subject matter there is provided a downhole device.

According to an embodiment of the second aspect, there is provided a downhole device comprising: the actuation mechanism according to at least one embodiment of the first aspect; and a catcher device which is configurable in a catching configuration in which a first element is being retained by the catcher device and a bypassing configuration in which a second element is being bypassed; wherein the second part is coupled to the catcher device for actuating the catcher device; wherein the catcher device is in the bypassing configuration if the second part is in the first position; and wherein the catcher device is in the catching configuration if the second part is in the second position.

According to a third aspect of the herein disclosed subject matter there is provided an operating assembly.

According to an embodiment of the third aspect there is provided an operating assembly comprising: an actuation mechanism according to the first aspect or at least one embodiment thereof; a downhole device according to the second aspect or at least one embodiment thereof, the actuation mechanism being provided for actuating the downhole device; and an actuation element having a diameter larger than the first clearance and smaller than the second clearance.

According to a fourth aspect of the herein disclosed subject matter there is provided a method.

According to an embodiment of the fourth aspect there is provided a method of operating a downhole device, the method comprising: providing an element in a fluid flow towards the downhole device; locating the element in a part defining a first clearance of a passageway, the element thereby at least partially obstructing the passageway; increasing a pressure of the fluid upstream the element to move the part from a first position into a second position by the increased pressure, wherein in the second position the part defines a second clearance of the passageway, the second clearance allowing the element to pass through the passageway.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

In the following, exemplary embodiments of the herein disclosed subject matter are described, any number and any combination of which may be realized in an implementation of aspects of the herein disclosed subject matter.

At least some of the aspects and embodiments of the herein disclosed subject matter are based on the idea that an actuating movement of a (second) part from a first position to a second position can be effected by (i) configuring a clearance of a passageway of the part depending on a position of the part and (ii) providing an element (herein also referred to as first element) having a suitable diameter to be caught by the part in the a position, move the part from the first position to a second position wherein in the second position the element is released from the part and passes through the passageway.

Further, at least some of the aspects and embodiments of the herein disclosed subject matter are based on the idea that an element (herein also referred to as first element) to be caught by a catcher device may be used to bring a catcher device into a catching configuration in which the catcher device is configured for retaining the element.

Further, at least some of the aspects and embodiments of the herein disclosed subject matter are based on the idea to replace a known mechanical coupling between a downhole tool and a catcher device by a utilization of the element to be caught to bring the catcher device into the catching configuration.

According to an embodiment of the first aspect, a downhole actuation mechanism is provided, the actuation mechanism comprising a first part having a guiding surface and a second part defining a passageway. According to a further embodiment, the second part is movable with respect to the guiding surface between a first position and a second position.

According to an embodiment, the movability of the second part is provided in an axial direction, wherein the axial direction is defined by a downhole string (e.g. a drillstring or a coiled tubing, just to name some examples) into which the actuation mechanism is included. In such an embodiment a position may be referred to as an axial position, e.g. the first position may be referred to as first axial position and the second position may be referred to as second axial position.

According to a further embodiment, the second part defines a first clearance of the passageway in the first position (i.e. when the second part is in the first position with respect to the guiding surface). According to a further embodiment, the second part defines a second clearance of the passageway in the second position (i.e. when the second part is in the second position with respect to the guiding surface), wherein the second clearance is larger than the first clearance.

Accordingly providing the second part as disclosed herein allows a suitably sized element to be retained by the passageway when the passageway defines the first clearance and allows the element to be passed through the passageway when the passageway defines the second clearance.

According to a further embodiment, the second part is a sleeve and the passageway extends through the sleeve. For example, the sleeve may be a collet.

According to a further embodiment, the second part is configured to be radially expandable from a first configuration to a second configuration. In particular, according to an embodiment the second part is configured to be radially expandable from the first configuration to the second configuration at least when the second part is in the second position. For example, according to an embodiment in the first position the guiding surface is acting on the second part so as to maintain the second part in the first configuration and in the second position the guiding surface allows the second part to expand into the second configuration.

According to an embodiment, the first part is a tubular body and the guiding surface is an interior surface of the tubular body. For example, according to an embodiment the first part comprises a hollow space and the second part is configured for being movable within hollow space of the first part.

According to an embodiment of the second aspect of the downhole device is provided, the downhole device comprising the actuation mechanism according to one or more embodiments of the herein disclosed subject matter. According to a further embodiment, the downhole device further comprises a catcher device which is configured for catching a first element. According to an embodiment, the first element is an activating element of a downhole tool, e.g. a circulating tool, which is located upstream the downhole device.

According to an embodiment, the catcher device is configurable in a catching configuration in which the first element is being retained by the catcher device and a bypassing configuration in which a second element is being bypassed. In other words, in the bypassing configuration the catcher device does not retain the second element.

According to an embodiment, when defining the first clearance the second part forms a seat for the first element.

According to a further embodiment, the downhole tool (which is located upstream the downhole device according to embodiments of the herein disclosed subject matter) also comprises a seat for receiving the first element. For example, according to an embodiment the first element may be configured so as to allow the first element to be pushed (e.g. sheared) through the seat of the downhole tool at the increased pressure (which may also be referred to as shearing pressure).

When pushing the first element through the seat of the downhole tool plastic deformation of the first element may occur. Accordingly, for a reliable operation of the actuation mechanism in such a case the seat formed by the second part has a configuration different from the seat of the downhole tool. For example, the seat of the downhole tool may comprise one or more protrusions which define the pressure that is necessary to push the first element through the seat (for example, according to an embodiment the downhole tool may be a drillstring valve as described in WO 2013/092532 A1). In such a case, the seat formed by the second part may have a different number of protrusions compared to the seat of the downhole tool (for example the seat formed by the second part of the actuation mechanism may have no protrusion).

According to an embodiment, the catcher device comprises a diverter, wherein the diverter is movable between a first diverter position and a second diverter position. Further, the catcher device may comprise a catching path and a bypass path besides the catching path. According to a further embodiment, the diverter includes an inlet and an outlet, wherein the outlet is fluidically coupled to the inlet, and wherein in the first diverter position the outlet is located facing the bypass path and in the second diverter position the outlet is facing the catching path.

According to an embodiment, the actuation mechanism is configured for moving the diverter between the first diverter position and the second diverter position. For example, according to an embodiment the actuation mechanism is mechanically coupled to the diverter.

According to an embodiment, a movement of the diverter between the first diverter position and the second diverter position includes a rotation of the diverter. For example, according to an embodiment the movement of the second part of the actuation mechanism is a movement is in a first direction (e.g. an axial direction) and the movement of the diverter between the first diverter position and the second diverter position is a rotation about the first direction, e.g. a rotation in a plane perpendicular to the first direction. For example, according to an embodiment the downhole device comprises a guiding mechanism which translates the axial movement of the second part of the actuation mechanism into a rotational movement of the diverter. For example, according to an embodiment the guiding mechanism may include a guide pin and guide groove arrangement as described in WO 2019/122004 A2.

According to an embodiment, the inlet of the diverter is fluidically coupled to the passageway of the second part. Accordingly, any element passing through the passageway (e.g. the first element or the second element) enters the inlet of the diverter and is hence routed either to the catching path or through the bypass path, depending on the position of the diverter.

According to an embodiment, the diverter and the second part are rotatably mounted with respect to each other, e.g. by a swivel coupling.

According to an embodiment of the third aspect an operating assembly is provided, the operating assembly comprising a downhole device according to the second aspect or at least one embodiment thereof, wherein the actuation mechanism is provided for actuating the downhole device; and the first element having a diameter larger than the first clearance and smaller than the second clearance.

According to an embodiment of the fourth aspect, a method of operating a downhole device comprises providing an element (herein also referred to as first element) in a fluid flow towards the downhole device (i.e. in a fluidflow in downstream direction). According to an embodiment, herein the term downstream refers to a direction of fluid flow from a pressuring device (e.g. on a surface of the earth) along the string which includes the actuating device. Further, according to an embodiment herein the term upstream refers to a direction opposite the downstream direction.

According to a further embodiment, the method of operating a downhole device comprises locating the element (also referred to as the first element) in a part (also referred to as the second part) defining a first clearance of a passageway. According to an embodiment, locating the element in the part includes pumping the element in a fluid flow towards the part. According to an embodiment, the element located in the part (e.g. in a seat of the part) at least partially obstructs the passageway to thereby increase a pressure of the fluid upstream the element. According to a further embodiment, the method comprises moving the part from a first position into a second position by the increased pressure, wherein in the second position the part defines a second clearance of the passageway, the second clearance allowing the element to pass through the passageway.

According to an embodiment, the downhole device comprises a diverter and a movement of the part from the first position to the second position operates the diverter (e.g. by a suitable configuration of the part and/or the diverter and/or by a coupling between the part and the diverter). According to a further embodiment, operating the diverter includes rotating the diverter. According to a further embodiment, the movement of the part is an axial movement along in axial direction and wherein operating the diverter includes rotating the diverter about an axis of rotation which is parallel to the axial direction.

According to embodiments of the first aspect, the downhole actuation mechanism is adapted for providing the functionality or features of one or more of the herein disclosed embodiments and/or for providing the functionality or features as required by one or more of the herein disclosed embodiments, in particular of the embodiments of the first, second, third and fourth aspect disclosed herein.

According to embodiments of the second aspect, the downhole device is adapted for providing the functionality or features of one or more of the herein disclosed embodiments and/or for providing the functionality or features as required by one or more of the herein disclosed embodiments, in particular of the embodiments of the first, second, third and fourth aspect disclosed herein.

According to embodiments of the third aspect, the operating assembly is adapted for providing the functionality or features of one or more of the herein disclosed embodiments and/or for providing the functionality or features as required by one or more of the herein disclosed embodiments, in particular of the embodiments of the first, second, third and fourth aspect disclosed herein.

According to embodiments of the fourth aspect, the method is adapted for providing the functionality or features of one or more of the herein disclosed embodiments and/or for providing the functionality or features as required by one or more of the herein disclosed embodiments, in particular of the embodiments of the first, second, third and fourth aspect disclosed herein.

According to embodiments of the herein disclosed subject matter, the catcher device may be provided in any degree of detail described in WO 2019/122004 A2.

In the above there have been described and in the following there will be described exemplary embodiments of the subject matter disclosed herein with reference to a downhole actuation mechanism, a downhole device, a operating assembly and a method of operating a downhole device. It has to be pointed out that of course any combination of features relating to different aspects of the herein disclosed subject matter is also possible. In particular, some features have been or will be described with reference to device type embodiments (e.g. relating to a downhole actuation mechanism, a downhole device or an operating assembly) whereas other features have been or will be described with reference to method type embodiments (e.g. relating to a method). However, a person skilled in the art will gather from the above and the following description that, unless otherwise notified, in addition to any combination of features belonging to one aspect also any combination of features relating to different aspects or embodiments, for example even combinations of features of device type embodiments and features of the method type embodiments are considered to be disclosed with this application. In this regard, it should be understood that any method feature derivable from a corresponding explicitly disclosed device feature should be based on the respective function of the device feature and should not be considered as being limited to device specific elements disclosed in conjunction with the device feature. Further, it should be understood that any device feature derivable from a corresponding explicitly disclosed method feature can be realized based on the respective function described in the method with any suitable device disclosed herein or known in the art.

The aspects and embodiments defined above and further aspects and embodiments of the herein disclosed subject matter are apparent from the examples to be described hereinafter and are explained with reference to the drawings, but to which the invention is not limited. The aforementioned definitions and comments are in particular also valid for the following detailed description and vice versa.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a cross-sectional view of a downhole device according to embodiments of the herein disclosed subject matter.

FIG. 2 shows part of the downhole device of FIG. 1 in greater detail.

FIG. 3 shows the downhole device of FIG. 1 with the second part in a second position.

FIG. 4 shows part of the downhole device of FIG. 3 in greater detail.

FIG. 5 shows part of the downhole device of FIG. 3 in still greater detail.

FIG. 6 shows part of the downhole device of FIG. 1 in a perspective view without the first part.

FIG. 7 shows part of the second part the downhole device of FIG. 6 in greater detail.

DETAILED DESCRIPTION

The illustration in the drawings is schematic. It is noted that in different figures, similar or identical elements are provided with the same reference signs. Accordingly, the description of the similar or identical features is not repeated in the description of subsequent figures in order to avoid unnecessary repetitions. Rather, it should be understood that the description of these features in the preceding figures is also valid for the subsequent figures unless explicitly noted otherwise. Further, sectional areas are only partly hashed to enhance readability of the drawings and reference lines.

FIG. 1 shows a cross-sectional view of a downhole device 100 according to embodiments of the herein disclosed subject matter.

According to an embodiment, the downhole device 100 comprises a downhole actuation mechanism 102 (also referred to as “actuation mechanism”) and a catcher device 104.

In accordance with an embodiment, the actuation mechanism 102 comprises a first part 106 having a guiding surface 108 and the second part 110 having a passageway 112. In accordance with an embodiment, the second part 110 is movable with respect to the guiding surface 108. According to an embodiment, the second part 110 comprises a sleeve 114. According to a further embodiment, the sleeve 114 of the second part 110 is coupled, e.g. mechanically coupled, to a sleeve 116, e.g. by a threaded connection 118. For example, according to an embodiment the sleeve 116 may be the sleeve of a downhole tool (not shown in FIG. 1 ). According to other embodiments, the second part 110 is decoupled from the downhole tool (not shown in FIG. 1 ). According to still further embodiments, the sleeve 116 is provided for biasing the second part 110 into a predetermined position, e.g. into the first position, e.g. as shown in FIG. 1 . To this end, a biasing element 158 may be provided, the biasing element 158 biasing the second part 110 into the predetermined position, e.g. the first position. According to an embodiment, the biasing element 158 may be provided in a dedicated sub 117, e.g. as shown in FIG. 1 , or may be included in the downhole device 100, just to name some examples.

According to an embodiment, the catcher device 104 is configurable in a bypassing configuration 120 in which an element, e.g. a second element 122, is bypassed, e.g. as shown in FIG. 1 . In accordance with an embodiment, the catcher device 104 comprises a diverter 124 which is movable between a first diverter position (corresponding to the bypassing configuration 120) and a second diverter position (not shown in FIG. 1 ).

According to an embodiment, the catcher device 104 comprises a catching path 126 and a bypass path 128. Further according to an embodiment, the diverter 124 comprises an inlet 130 and an outlet 132 which is fluidically coupled to the inlet 130, e.g. as shown in FIG. 1 . According to an embodiment, in the first diverter position (bypassing configuration 120) the outlet 132 is facing the bypass path 128, e.g. as shown in FIG. 1 .

According to an embodiment, the second part 110 is coupled to the diverter 124, e.g. mechanically coupled. For example, according to an embodiment the second part 110 is coupled to the diverter 124 by a swivel coupling. According to a further embodiment, the inlet 130 of the diverter 124 is fluidically coupled to the passageway 112 of the second part 110, e.g. as shown in FIG. 1 . For example, according to an embodiment the inlet 130 is located facing the passageway 112, e.g. as shown in FIG. 1 .

According to an embodiment, a straight movement of the diverter 124 (e.g. in an axial direction 134 such as in a direction parallel to the guiding surface 108) includes a rotation of the diverter 124. For example, according to an embodiment the diverter 124 is configured such that the straight movement of the diverter 124 necessarily involves (leads to) the rotation of the diverter 124. For example, according to an embodiment the diverter 124 and its surrounding surface 136 are provided with a guide pin and guide groove arrangement. For example, according to an embodiment the guide grooves may be provided in the outer surface 138 of the diverter 124 (e.g. such as the guide grooves 140 shown in FIG. 1 ). According to an embodiment, the guide groove is helically with respect to the axial direction 134, thus resulting in the rotation of the diverter 124 upon straight movement of the diverter 124 in the axial direction 134.

FIG. 2 shows part of the downhole device 100 of FIG. 1 in greater detail.

According to an embodiment, the second part 110 defines a clearance 141 of the passageway 112. In accordance with an embodiment, the clearance 141 is a first clearance 142 in a first position 144 of the second part 110. According to an embodiment, in the first position 144 the second part 110 forms a seat 143, wherein the seat 143 defines the first clearance 142, e.g. as shown in FIG. 1 .

According to an embodiment, the second part 110 includes a wear ring 146 on the exterior of the second part 110 in order to eliminate or at least reduce the possibility of the second part wedging with the guiding surface 108. The first position 144 of the second part 110 corresponds to a first diverter position 145. According to an embodiment, the first diverter position 145 corresponds to a first angular position of the diverter 124. Since according to an embodiment, the outlet 132 of the diverter is located radially offset from an axis of rotation 147 of the diverter 124, e.g. as shown in FIG. 2 , the position of the outlet 132 is changed by rotating the diverter 124.

According to an embodiment, the second part includes at least one cutout 148 and/or two or more segments 150, e.g. a plurality of segments 150, e.g. as shown in FIG. 2 , thus allowing the clearance 141 defined by the second part 110 to expand from the first clearance 142 to a second clearance (not shown in FIG. 2 ) which is larger than the first clearance if such an expansion is not inhibited. According to an embodiment, the segments 150 define an end portion of the second part 110. Further according to an embodiment, the segments 150 define the seat 143 if the second part 110 is in the first position 144. According to an embodiment, the segments 150 together define a continuous seating surface (i.e. at least in the portions that define the seat neighboring segments contact each other if the second part 110 is in the first position).

According to an embodiment, the configuration in which the second part 110 defines the first clearance 142 is referred to as first configuration and the configuration in which the second part 110 defines the second clearance is referred to as second configuration. For example, according to an embodiment the guiding surface 108 is configured for configuring the second part so as to define the first clearance of the passageway in the first position, e.g. as shown in FIG. 2 . For example, according to an embodiment in the first position the guiding surface is inhibiting the second part to expand and thus define the second clearance of the passageway. In other words, according to an embodiment in the first position the guiding surface is acting on the second part 110 so as to maintain the second part 110 in the first configuration. According to a further embodiment, the guiding surface 108 comprises a recess 152 which allows the second part to expand and define the second clearance of the passageway, if the second part is in the second position. According to an embodiment, the recess 152 is an annular recess, e.g. as shown in FIG. 2 . According to a further embodiment (not shown in FIG. 2 ) the recess 152 may comprise two or more recess portions, e.g. three, five or ten recess portions and the second part may comprise corresponding protrusion portions which are capable of moving into the recess portions to thereby expand the second part.

According to an embodiment, the sleeve 116 and the second part 110 overlap each other, e.g. as shown in FIG. 2 . For example, according to an embodiment the sleeve 116 overlaps even with the segments 150 of the second part, e.g. as shown in FIG. 2 .

FIG. 3 shows the downhole device 100 of FIG. 1 with the second part 110 in a second position 154. However in the configuration shown in FIG. 3 the second part has not yet fully expanded and hence, as depicted in FIG. 3 , does not yet define the second clearance of the passageway 112.

In accordance with an embodiment, moving the second part 110 into the second position 154 is effected by providing a first element 156 in the second part 110, wherein the first element 156 has a diameter larger than the first clearance 142. Accordingly, when the second part 110 is in the first position 144 (see for example FIG. 2 ), the first element 156 is inhibited from passing through the (entire) passageway 112 but is rather caught by the passageway 112, e.g. as shown in FIG. 3 . Hence, a passageway portion 155 upstream the first element 156 can be pressurized, e.g. up to a predetermined increased pressure. This pressure can move the second part 110 downward against the action of a biasing element 158, e.g. a spring, e.g. as shown in FIG. 3 . According to an embodiment, the biasing element 158 is biasing the second part towards the first position 144 (see FIG. 1 ).

By the movement of the second part into the second position 154 also the diverter 124 has moved in axial direction 134 and, by virtue of the guide pins (not shown) and guide grooves 140, has been rotated into the second diverter position 160 in which the outlet 132 of the diverter is located facing the catching path 126, e.g. as shown in FIG. 3 . Accordingly, in accordance with an embodiment, if the second part 110 is in the second position 154, the diverter 124 is in the second diverter position 160, e.g. as shown in FIG. 3 .

It should be understood that the first element 156 may be followed by further elements 157, e.g. as shown in FIG. 3 . For example, according to an embodiment the first element 156 may be an activation element of a downhole tool, for example a downhole valve providing a bypass flow upon activation by the actuation element, e.g. a downhole valve as described in U.S. Pat. No. 4,889,119. In such a case, the further elements 157 may be for example deactivation elements which are provided for closing bypass ports and deactivation of the bypass flow.

FIG. 4 shows part of the downhole device 100 of FIG. 3 in greater detail.

According to an embodiment, in the second position 154 the second part 110 can expand into a recess 152, thus allowing the second part to define a second clearance of the passageway 112, wherein the diameter of the first element 156 is smaller than the first clearance. As noted with regard to FIG. 3 , in FIG. 3 and FIG. 4 the second part 110 is not fully expanded yet and hence does not yet define the second clearance.

According to a further embodiment, the mechanical the coupling between the second part 110 and the diverter 124 is configured so as to allow the second part 110 to expand and the thus provide the second clearance of the passageway 112. For example, according to an embodiment, the second part 110 has a portion 162 which is located with sufficient free radial motion in a recess 164 of the diverter 124. In order to provide a mechanical coupling in the axial direction 134, a pin and groove arrangement may be provided, e.g. by providing a groove 166 in the second part 110 and by providing a pin 170 in the diverter 124, e.g. as shown in FIG. 4 .

FIG. 5 shows part of the downhole tool of FIG. 3 in still greater detail.

According to an embodiment, a shape of the recess 152 (of the guiding surface 108) at least in part corresponds to (e.g. is mating with) the shape of the second part 110 in a region 172 facing the recess 152, e.g. as shown in FIG. 5 . According to an embodiment, the second part 110 comprises a protrusion 174 that protrudes over a body 176 of the second part 110 in a radial direction 173, perpendicular to the axial direction 134. By providing the protrusion 174 manufacturing tolerances for the body 176 are less relevant and the area that has to be adapted to the guiding surface 108 and/or the recess 152 can be kept small which reduces manufacturing efforts, e.g. a machining time. According to an embodiment, the region 172 is facing the recess 152 in the second position 154 of the second part 110.

According to an embodiment, the wear ring 146 is provided on the protrusion 174.

According to a further embodiment, the protrusion comprises a stop face 178 which is abutting the diverter 124. According to an embodiment, the stop face 178 protrudes from the protrusion 174 in axial direction 134, e.g. as shown in FIG. 5 .

According to an embodiment, the passageway 112 comprises a restriction 175 which defines the clearance 141 of the passageway 112. According to an embodiment, the restriction 175 is located radially opposite the protrusion 174, e.g. radially inwardly with respect to the protrusion 174, e.g. as shown in FIG. 5 . According to a further embodiment, bulk material is provided between the radially outer surface of the protrusion (region 172) and the radially inner surface of the restriction 175, e.g. as shown in FIG. 5 . This provides a reliable force transfer between the first part 106 and the radially inner surface of the restriction 175. Hence, the profile (including the recess 152) of the guiding surface 108 thus reliably defines the clearance of the passageway 112 of the second part 110 (e.g. reliably defines inter alia the first clearance in the first position 144 and the second clearance in the second position 154).

According to an embodiment, the sleeve 116 overlaps with the cutouts 148, e.g. as shown in FIG. 5 . Since in an embodiment the second part 110 is exposed to flow (e.g. flow of drilling fluid) over long periods of time (e.g. during any operation in which fluid is routed past the actuation mechanism, e.g. during drilling, during split flow circulating operations etc.) the second part and in particular the cutouts 148 are susceptible to erosion in such a case. Further, according to an embodiment, the body 176 is at least partly flexible. In such a case, material treatment and/or heat treatment of the body 176 may adversely affect the body 176. An overlap of the sleeve 116 with the body 176 may reduce adverse effects, e.g. adverse effects on the body 176 due to at least one of exposure to flow/material treatment/temperature treatment. According to an embodiment, the sleeve 116 (e.g. an axial end face of the sleeve 116) is abutting (e.g. is making contact with) the body 176, e.g. with an axial end face of the body 176, e.g. as shown in FIG. 5 .

FIG. 6 shows part of the downhole device 100 of FIG. 1 in a perspective view without the first part 104.

In particular, FIG. 6 shows the diverter 124, the second part 110 and the sleeve 116. The individual elements discussed above have been denoted by the same reference signs in the description thereof is not repeated here.

FIG. 7 shows part of the second part 110 of FIG. 6 in greater detail.

According to an embodiment, the wear ring 146 (not shown in FIG. 7 ) is located in a groove 177 in the protrusion 174. According to an embodiment, each of the segments 150 is supported by an elongated part 180. The elongated parts 180 together form part of the body 176. Between two of the elongated parts 180 the cutout 148 is provided, e.g. as shown in FIG. 7 , thus providing radial movability to the segments 150 (e.g. by providing flexibility of the elongated parts 180, e.g. as shown in FIG. 7 ). In other words, the elongated parts are spaced from each other in circumferential direction, e.g. as shown in FIG. 7 . According to an embodiment, the elongated parts 180 extend from a common piece 182, e.g. as shown in FIG. 7 . The common piece may include for example a thread 184 which may be used for the threaded connection 118 between the second piece 110 and the sleeve 116 (if the actual implementation uses a sleeve 116 (not shown in FIG. 7 )).

According to an embodiment, the segments 150, the body 176 (e.g. the elongated parts 180) and the common piece 182 are formed from a single piece of material, e.g. as shown in FIG. 7 . According to other embodiments (not shown), the segments 150, the body 176 and the common piece 182 are at least partially from individual elements which are attached to each other so as to form the second part 110 according to embodiments of the herein disclosed subject matter.

It should be noted that any entity disclosed herein (e.g. components, elements and devices) are not limited to a dedicated entity as described in some embodiments. Rather, the herein disclosed subject matter may be implemented in various ways and with various granularity on device level while still providing the specified functionality. Further, it should be noted that according to embodiments a separate entity may be provided for each of the functions disclosed herein. According to other embodiments, an entity is configured for providing two or more functions as disclosed herein. According to still other embodiments, two or more entities are configured for providing together a function as disclosed herein.

Further, it should be noted that while the exemplary downhole devices and actuation mechanisms in the drawings comprise a particular combination of several embodiments of the herein disclosed subject matter, any other combination of embodiment is also possible and is considered to be disclosed with this application and hence the scope of the herein disclosed subject matter extends to all alternative combinations of two or more of the individual features mentioned or evident from the text. All of these different combinations constitute various alternative implementations of the herein disclosed subject matter.

It should be noted that the term “comprising” does not exclude other elements or steps and the “a” or “an” does not exclude a plurality. According to an embodiment, the term “comprising” includes the meaning “consisting of”. According to a further embodiment, the term “comprising” includes the meaning “comprising inter alia”. Also, elements described in association with different embodiments may be combined. It should also be noted that reference signs in the claims should not be construed as limiting the scope of the claims.

According to an embodiment the term “adapted to” includes inter alia the meaning “configured to”. Further, herein the disclosure of a function which is performed by an entity implicitly discloses that according to an embodiment the entity is configured to perform the function.

In order to recapitulate some of the above-described embodiments of the herein disclosed subject matter one can state: Provided is an downhole actuation mechanism, the actuation mechanism comprising: a first part having a guiding surface; a second part defining a passageway; the second part being movable with respect to the guiding surface between a first position and a second position; the second part defining a first clearance of the passageway in the first position; the second part defining a second clearance of the passageway in the second position, the second clearance being larger than the first clearance. 

1. An downhole actuation mechanism, the actuation mechanism comprising: a first part having a guiding surface; a second part defining a passageway; the second part being movable with respect to the guiding surface between a first position and a second position; the second part defining a first clearance of the passageway in the first position; the second part defining a second clearance of the passageway in the second position, the second clearance being larger than the first clearance.
 2. The actuation mechanism according to claim 1, wherein the second part comprises a sleeve; and wherein the passageway extends through the sleeve.
 3. The actuation mechanism according to claim 1, wherein the second part is configured to be radially expandable from a first configuration to a second configuration; wherein in the first position the guiding surface is acting on the second part so as to maintain the second part in the first configuration; and wherein in the second position the guiding surface allows the second part to expand into the second configuration.
 4. The actuation mechanism according to claim 1, wherein the first part is a tubular body; and the guiding surface is an interior surface of the tubular body.
 5. A downhole device comprising the actuation mechanism according to claim 1; and a catcher device which is configurable in a catching configuration in which a first element is being retained by the catcher device and a bypassing configuration in which a second element is being bypassed; wherein the second part is coupled to the catcher device for actuating the catcher device; wherein the catcher device is in the bypassing configuration if the second part is in the first position; and wherein the catcher device is in the catching configuration if the second part is in the second position.
 6. The downhole device according to claim 5, wherein the catcher device comprises a diverter.
 7. The downholed device according to claim 6, the diverter being moveable between a first diverter position and a second diverter position; the catcher device comprising a catching path and a bypass path besides the catching path; wherein the diverter includes an inlet and an outlet; wherein the outlet is fluidically coupled to the inlet; wherein in the first diverter position the outlet is located facing the bypass path; and wherein in the second diverter position the outlet is facing the catching path.
 8. The downhole device according to claim 7, wherein a movement of the diverter between the first diverter position and the second diverter position includes a rotation of the diverter.
 9. The downhole device according to claim 7, wherein the inlet of the diverter is fluidically coupled to passageway of the second part.
 10. The downhole device according to claim 6, wherein the diverter and the second part are rotatably mounted with respect to each other.
 11. An operating assembly comprising: a downhole device according to claim 5, the actuation mechanism being provided for actuating the downhole device; and the first element having a diameter larger than the first clearance and smaller than the second clearance.
 12. A method of operating a downhole device, the method comprising: providing an element in a fluid flow towards the downhole device; locating the element in a part defining a first clearance of a passageway, the element thereby at least partially obstructing the passageway; increasing a pressure of the fluid upstream the element to move the part from a first position into a second position by the increased pressure, wherein in the second position the part defines a second clearance of the passageway, the second clearance allowing the element to pass through the passageway.
 13. The method according to claim 12, wherein the downhole device comprises a diverter and wherein a movement of the part from the first position to the second position operates the diverter.
 14. The method of claim 13, wherein operating the diverter includes rotating the diverter.
 15. The method of claim 13, wherein the movement of the part is an axial movement along in an axial direction and wherein operating the diverter includes rotating the diverter about an axis of rotation which is parallel to the axial direction. 